Heat the sugar and water to boiling in a Dutch oven, stirring occasionally. Boil and stir for 1 minute more then remove from the heat. Stir in the limeade concentrate, lemon juice, and food colorings. Add the fruit pectin and skim off the foam. Immediately pour into hot sterilized jars, glasses, or freezer containers. Cover tightly and cool to room temperature. Store no longer than 4 weeks in the refrigerator or 2 months in the freezer. Makes six 5-oz glasses of jelly.